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The application of precision agriculture in cocoa and papaya cultivation in Brazil is still incipient. This study aimed to evaluate the spatial variability of the physical attributes of soil cultivated with a consortium of papaya and cocoa. The study was conducted in two sampling grids of 50 points, in two areas cultivated with papaya and cocoa with different planting times (three and eleven months). The soil attributes soil resistance to penetration (RP) and soil gravimetric moisture (UG) were determined at soil depths of 0–20, 20–40 and 40–60 cm. The data were submitted to an exploratory and descriptive analysis. Subsequently, a geostatistical analysis was performed to quantify spatial dependence and then interpolation of the data through kriging. The maps showed weak spatial variability for the UG and RP. In the two areas, it was observed that the depth of 0–20 cm had a lower RP (1.7 Mpa) and a higher UG (40 g g−1), and as the depth was higher, had a higher RP (4.4 Mpa) and a lower UG (38 g g−1). Area 1 presented higher RP values in depth, showing greater susceptibility to compaction. The area characterized by the consortium of papaya and cocoa presented more susceptible to compaction. The mechanical resistance of the soil to penetration was more critical in the 40–60 cm layer for the two consortia evaluated, evidencing areas with possible restriction to plant growth. [ABSTRACT FROM AUTHOR]

Oil palm production is strategic in the Amazon with high productive potential, but information on its fertilization is still relatively scarce for the region. The objective of this work was to evaluate the effects of phosphorus, potassium and magnesium fertilizations on oil palm production in different years in the state of Pará, Brazil. The study was conducted in Tailândia, Northeastern of Pará, Eastern Amazon, Brazil. A randomized block design was used in a 4 x 2 x 3 x 2 factorial scheme, with four levels of phosphorus, two sources of phosphorus, three levels of potassium and two levels of magnesium. Oil palm production responded positively to the increase in phosphorus levels, and until the eighth year of age of the plants, there was greater production when triple superphosphate was applied. From the ninth year onwards, fertilization with phosphine provided a production equal to the supply of phosphorus with triple superphosphate. The application of potassium chloride increased the number, weight and production of the bunches from the sixth year. The supply of magnesium sulfate increased the average weight of the bunches. Thus, phosphorus, potassium and magnesium fertilizations become essential to increase oil palm production in the Northeast of Pará. [ABSTRACT FROM AUTHOR]